1. Field of the Invention
This invention relates to a movable contact body employed for an operating panel of various electronic equipment (hereinafter referred to as "a panel switch movable contact body"), and to a panel switch using the movable contact body.
2. Description of the Related Art
A conventional panel switch movable contact body, and a panel switch using the movable contact body, will be described with reference to FIGS. 8A, 8B and 9A, 9B.
FIGS. 8A and 8B are an exploded perspective view, and a sectional view, respectively, showing a conventional panel switch movable contact body. In those figures, reference numeral 1 designates a dome-shaped movable contact made of a thin, elastic, metal plate; and 2, a spacer of insulating film. An adhesive agent 2A is applied to the lower surface of the spacer 2, so that a separator 3 is bonded to the lower surface of the spacer 2. The spacer has a plurality of holes 2B, in which the movable contacts 1 are inserted. Each of the movable contacts 1 is upwardly curved (dome-shaped), and secured to the upper surface of the spacer 2 with its upper surface covered with an insulating film sheet 4 whose lower surface is applied with an adhesive agent 4A.
Reference numeral 5 denotes a protective sheet of insulating film adapted to protect the movable contacts 1 and prevent the corrosion of the latter 1 by the gases in air or the sticking of foreign matters thereto. An adhesive agent 5A is applied to the upper surface of the protective sheet 5, so that the latter 5 is bonded to the lower surface of the spacer 2 through a separator 3. That is the protective sheet 5 covers the lower surfaces of the movable contacts 1, thus completing a panel switch movable contact body 10.
FIGS. 9A and 9B are an exploded perspective view and a sectional view, respectively, showing a panel switch employing the conventional panel switch movable contact body. In those figures, reference numeral 6 designates a wiring board (or printing circuit board) having central stationary contacts 6A and outside stationary contracts 6B on the upper surface. The protective sheet 5 and the separator are removed from the panel switch movable contact body 10A. That is, the resultant movable contact body 10A is bonded to the wiring board 6 through the adhesive agent 2A in such a manner that the outer periphery of each of the movable contacts is on the respective outer stationary contact 6B, and the central top thereof is confronted with the respective central stationary contact. Thus, the panel switches 11 have been manufactured.
A push button 7 of flexible rubber or resin is set above each of the panel switch thus manufactured. When the operating section 7A of the push button 7 is depressed, a depressing portion 7B formed on the lower surface of the operating section 7A is caused to depress the movable contact 1 through the sheet 4. As a result, the movable contact 1 performs reverse motion, so that the central part thereof is brought into contact with the central stationary contact 6A; that is, the central stationary contact 6A of the wiring board 6 is electrically connected to the outside stationary contact 6B. Upon release of the push button 7, the elastic restoring force of the movable contact 1 acts to disconnect the central part of the movable contact 1 from the central stationary contact 6A; that is, the panel switch is turned off as shown in FIG. 9B.
However, the above-described conventional panel switch movable contact body, and panel switch using the movable contact body suffer from the following difficulties: It employs the movable contacts 1, sheets 4, spacer 2, protective sheet 5, and so forth. That is, the number of components is relatively large, and the number of steps of bonding those components is also large. Hence, the switch assembling work is rather troublesome. As a result, the resultant panel switch is high in manufacturing cost. Furthermore, static electricity is liable to sneak in various electronic equipment through the panel switches. Hence, on the side of the electronic equipment, it is necessary to devise a counter-measure against it.